Telephone-exchange system



March 24, 1925. 1,531,046

D. L. TEMPLE TELEPHONE EXCHANGE SYSTEM Filed Oct. 23, 1922 2 Sheets-Sheet 1 .WOL

March 24, 1925. 1,531,046

D. L. TEMPLE TELEPHONE EXCHANGE SYSTEM Filed Oct. 23. 1922 2 shuts-Sheet 2 y MMA ff ,yi

Patented Mar. 24, 19,25. l

UNITED sfrATEs y 1,531,046l PVA-TENT .oF-Flor..v

nAvIn L. TEMPLEQQP NEW YORK, N. Y., AssIGNOR. To WESTERN ELECTRIC COMPANY,

INCORPORATED, or' NEW YORK, N. Y.,' A CORPORATION OP NEW YORK.'

TELEPHONE-EXCHANGE SYSTEM.

Application le'd October 23, 1922. Serial No. 596,204.

To all whom t may] concern: 1

Be it known that I, DAVID L. TEMPLE, a citizen ofthe United States, residing at New York, in the county of New York,

I State of New York, have invented certainl new and useful Improvementsin Telephone- ExchangeSystems, of whichthe following is a full,clear,` concise, .,and'exact description.

This invention relates to telephone `ex-` change systems, and particularly to an arrangement for observing andtesting for temporary unstandard .conditions o n subscribers lines or central office `equipment 151 in exchanges provided with automatic,

switches.

Grounds or crossed lines of very` .brief duration may occur Ona subscribers line or on central oilice equipmentldue to a variety rof causes. The'touching of bare` conductors in a wind storm, worn insulation permitting contactorigrounding by trees, vibration and so on, may bementioned as examples. When such grounds occur in an `manual means', the Occasional flashing of the line lamp will attract the Operators` attentiony who can report and cause the trouble to be remedied. In exchanges in which :connections are made by automatic switches there is no such means for indieating brief grounds, and the condition may result in more or less serious interference. with service and consequent complaints, while the ordinary testing or `indicating temporary grounds or crossed lines, which` signal is so operated as to enables an attendant to distinguish between a normal call, a temporary groundvor crossV on the.

subscribers line, andA a temporary ground or cross on the subscribers rcentral oli'ice equipment. y

A feature ofthe invention is the provision of means tov indicate such unstandard con- 5 `ditions for lines served either byline exchange in which connections are made by switchesor by' the line finders, or for .either individual lines-ortho lines of a P., B. X. group when served 'by the line finders or line switches.. y Y Another feature of the invention resides 1n the provisionof means whereby` an operator may variably adjust the testing apparatus so thatit will function correctly,l irrespective of the characterfof the switching device used in establishing connection between. the line under consideration and an idle trunk. 'y Other and further features of the invention will become apparent from a consider ation ofthe following description and the appended claims.

Referring to the drawing Figs. 1 and 2, when arranged withy Fig. 2 below Fig. 1, illustrate a portion of an automatic telephoner exchange to which the circuits and apparatus embodying the present invention are adapted. Fig.y 1 shows in the upper portion, a subscribers line incoming to the central `oiiice `where it is extended through the distributing frames to an individual line switch. lA first or district selector, revister sender and trunk outgoing from' the trict selector, are also indicated diagrammatically. In the lower Jpart of the figure a similar showing is made of another subscribers line incoming to thev central OfIice, which line is extended to a district selector bymeans of a line finder. An arrangement bywhich the line and central office `conductors may be extended through to jacks leading to the testing circuits is illustrated. Fig.-2 shows the circuits and apparatus by which the visual signal is controlled and jacks by means of which tests may be made. The apparatus in the lower) right hand dotted rectangle is used when the line under observation is connected to aline switch, the apparatus in the lower lefthand rectangle is used when the line is served by a line finder, and the apparatus above the dotted line is used in connection with both types of connections, v

Reference .may be made to U. S. Patent No. 1,393 ,728v` S. B. Williams Jr., granted i October 11, 1921 for the disclosure of a complete telephone exchange system employing vline finders, and to U. S. Patent No.

1,395,977, F A. Stearn and F. J. Scudder, granted November 1, 1921, for' the disclosurel of a complete telephone exchange ldissystem employing line switches, @with which systems the circuitslan-d apparatus :of the present invention are adapted to be used.

.lfVhem from subscribers complaints 0r for 'otherk reasons it is suspected that intermittent grounds or crossesare occurring on one or more lines, the heat coils ofsuch lines are removed and spring plugs, such as 113 or 114, areinserted in their place. To these plugs are Vconnected plugs, such as 107 and-108 orv k110 and 111, for-connecting the `lines lto vthe central office equipment through an indicating circuit, such as shown in Fig. 2 by means of jacks 101 and 1'02 -or 104.- and 105, which jacks may be located at any convenient point, preferably near `the distributing frames. The indicating circuit ofFig. 2isindividually associated with a line during lthe time it is lconnected. with it. The jacks, such as 1031 or 106, are provided to receive plugs, suchv as 109er v112,

one Wire of which is connected to the sleeve conductor ofthe line at the intermediate distributing frame, and theother toa clip connector which is fastened to the armature of the line relay. The jacks Aand lamps -or several indicating circuits, such as shown in Fig. 2, appear at an attendants-des'k Where, as more fully described belo\v,brief grounds or cross connections appear as momentary lighting of the various lamps, and from which tests maybe made,

` The operation of the circuits when connected to a-subsc'ribersline served by a line switch "will first be described.'A Springplug 113 is inserted in placejof the heat coils 100 at the distributing t'rame conductorl 123 is connected to the testconductor at lthe intermediate distributing iframe, and con-` ductor 1124 clipped to the right hand varniature ofthe line relay 125;plugs 107, 108

and 109 are inserted in j'acks101, 102l and 103 respectively, closing ground to conductor 126, Key v200 is open at this time,

If, now, the subscriber" initiates a call by'lifting his receiver from the hoolg'a circuit is closed from grounded battery, right hand Winding of* the relayv 207, inner lright hand armature and back cont-act of vrelay 'i 208, conductor 209, upper -closedcontact of jack 202, conductor 131, sleeve'of jack '102, sleeve of plug 108, conductor 122, conductor 116, through substation. 11, conductor 115, conductor 121, tip of plug 108, tip contact of jack 102, conductor 132, lower closed contact of jack 202, conductor 210,v

inner left hand armature and back contact of relay 208, left hand Winding of relay 207 to ground. Relay 207 is energized and'at its right hand armature closes an obvious circuit for green` lamp 206. At its left hand armature relay 207 closes a circuitfor line relay 125 Which may be traced from grounded battery, right hand Winding of `relayv 125, inner right hand armatureand beekfeliwet Otirelay lmxumnerwire 1283 conductors "119', 130 and 2 2, left hand armature land front contact 'of relay 207, conductors- 211, 129- and-.120, jumper wire. .1.27,

left `hand .armatureand back contact 0f relay 140 to ground.

The-energizlation of relay 125 in the above traced circuit causes the operation of the line switch 133 Ltoysclect an idle district selector 134 and the advance of the district selector sequence fswitch from position l-1 into position 2, during which L'the selection of an idle sender takes .place Without .further vaction on the part lof the subscriber.

If, noW,1the `subscriber `lails fto operate his dial,the district selector'remains in-position 2 and atime alarm circuit (not shown) functions "to-notify *the attendant. This time alarm `scheme forms no part of the present invention and therefore Will notbe described.y '.Should aground occur on the .f

conductor 115,y or a lcross-connection"between the conductors 115 `andj116r of suflicient duration, -the .operation will proceed as above outlined. c f

At the time plug 107 was inserted in jacl; 101,-a circuit was completed for high resistance `relay .213, which may be 'traced from grounded battery, resistance 214, outer left Ahand armature' and back contact of relay 208, inner right hand armature .and back contact of relay 215.conductors 216` and 217, outer "left-'hand armaturey and back contact ofrelay 218, winding of relay 213,k conduct0rs`219, 211,129 and 120,'jumper Wire 12,7, v*left lfhandgarmature and :back contact- Ltending, from 'groundedbattery, Winding of relay 221, armature and front contact of relay 220 to ground. l

When now. the relay 125 operates it closes a direct ground romthe first two contacts on a line switch arc (not shown) to its right hand `armature, whichr ground starte the' line switch and shunts ythe relay 220.y Relay 220 vdeenergizes 'and'completes a cir'- cuit from grounded battery, left hand wind-l ing of relay 222, conductor 223, armature and front contact of relay 213, armature an'dfbackcontactof relay 220 to ground. Relay 1222 energizes and locks `up in a circuit extending from grounded battery, resistance' 214, outer left hand armature and back contact of relay 208, inner right hand armature and back contact of relayA 215, conductor 216, right hand armature and front contact of relay 222, right hand wind-l ing of relay 222 to ground. Relay 222 closes at its left hand armature an'` obvious circuit for lighting the white lamp 205.

As soon as the line switch advances two steps,` the ground at the front contact of the righthand armature of relay 125 is broken and relay 220 again energizes, but relay 221 being slow to release, holds its armature at tracted during this deenergization and also during the deenergization of 220 at each step of the line switch in seeking an idle district selector. 1When an idle district selector has been found, battery potential is connected to conductor 137, thus completing a circuit for the energizationof relay 140, Y

by way of the left hand armature and winding of relay 125 and right hand winding of relay 140 to ground. Relay 140 energizes, and at its left hand and inner right hand armatures, opens the circuit for relay 125; at its outerright hand armature opens the circuit for the stepping magnet 135, and at its intermediate righthand armature closes a locking circuit for itself. The deenergization of relay 125 completes a shunting circuit for relay 220which` extends by way of the right hand armature and back contact of relay 125 to off-normal contact 138. which shunt is maintained throughout` the duration of the call. Therefore, relay 220 deenergizes for asulficient length `of time to permit relay 221 to deenergize. The deenergization of relay 221 closes a circuit from grounded conductor 126, armature and back contactof relay 221, outer right hand armature and back contact of relay 218, winding of relay 208 to grounded battery. Relay 208 energizes, and at its inner armatures opens the circuit for relay 207 and closes the line through to the central oilice equipment. The deenergization of relay 207 opens the circuit for lamp 206. At its outer left hand armature, relay 208 opens .the circuits of relays 222 and 213, which relays deenergize andrelay 222 opens the circuit of the lamp 205. At its outer right hand armature, relay 208 closes an obvious circuit for red lamp 204. therefore, the red lamp 204 is displayed alone during the conversation. At the kcompletion of conversation, magnet 135 steps the line switch back to normal when the shunting circuitl for relay 220 is opened. and that relay energizes, causing the energization of relay 221 and the opening of the circuit of relay 208 thus eX- tinguishing lamp 204.

If a prolonged cross or a ground occurs while the line is connected to the indicating circuit, the lamps are lighted in the saine `manner as with a regular call, whenr the subscriber fails to dial; and other means,`

.effec-t the apparatus at all would cause relay 207 to operate and light the green lamp momentarily. A slightly longer grounding of the line would also permit the operation of relay 125, Athe shuntinglof relay 220 and the operation of relay 222 to light the green and white lamps. Should the ground disappear before relay 222 becomes locked up, i

both white and green lamps would go out. Should the ground on the `line continue long enough to start the hunting movement of the line switch, but disappear before an idle district selector has been found, relay 207 deenergizes causing in turn thedeenergization of relay 125 and the return of the line switch to normal. During the huntingl operation of the line switch, the circuit of relay 220 lhas not been shunted or opened for a long enough period to permit the deenergization of relay 221. The circuit for energizing relay 208 will not be closed and 'relay 222 will remain locked up, and the lamp 205 lighted until the attendant re-.

leases it by the application of battery tential to the sleeve of one of the jacks 201, 202 or 203 and the operation/of relay 215 opens the circuit of relay 222.

f A somewhat longer grounding of the line might permit the selection of an idle dis` trict selector, resulting in the brief lighting of the three lamps but disappear before the district selector found an idle sender under which circumstances the district `selector. would restore to normal and the red lamp go out. v e

Should a ground or crossconnection ocn cur within the central office, relay 125 would beoperated, shunting relay 220` and causing the operation of relay 222 to light the" lamp 205 momentarily. Should this groundexistlong enough to permit the se` lection of an idle district selector, the operation of relay 140` will release relay 125, shunting relay 220 to permity the deenergization` of relay 221 and the energi'zation of relay 208. The` white lamp is extinguished and the red lamp lighted as before.

` If the substation A is selectedv as -a 'i for relay 208 from grounded battery, winding of relay 208, armature and back contact of relay 218, armature and back Contact of relay 221 to grounded conductor 126. Re-A lay 208 energizes, lights lainp- 204, and closes the line conductors through tothe central oice. The energization of relay 140 also opens at its left hand armature "the circuit of relay 213 so that relay 213, re-y leases its front Contact before relay 220 has had time to close its back contact, and relay 222 is not operated to light. lamp 205. Therefore, the red lamp 204 alone is displayed on calls terminating at the substation yunder observation.

VWhen making tests on the line A the insertion of a plug in one of the jacks 201, 202, or 203 connects battery to the sleeve of the jack and thence by conductor 229, normally closed contact of relay 232, Winding of relay 215 to ground. Relay 215 operates closing a circuit from grounded battery, resistance 214, outer left hand. armaturey and back contact of rela-y 208, inner left hand armature and front contact of relay 215, conductors 227, 128, windings of rrelay 140 to ground operating relay 140 to make the line of substation A busy to incoming calls. Relay 215 at its outer left hand armature closes the circuit for lanip 204 to indicate that the line is busy.

If the line should be busy when a testis attempted, the insertion `of the plugs and operation of relay 215 would be. of no eii'ect. As soon,`hovvever, as relay 140 releases, relays 220 and 221 operate again. Relay 208 `releases and closes battery to its outer left hand armature, thus completing the circuit above traced, for the operation of relay 140 to make the line busy and to permit the making of the ldesired test. The operation of relay 140 again opens the circuit of relay 220. However, the operation of relay215 has closed a locking circuit from grounded battery, Winding of relay 221, conductor 228, outer right hand armature and front contact of relay 215, armature and front contact of relay 221 to grounded conductor 126, preventing the reoperation of relay 208 and the alternate energization and deenergization oftliis-relay and relay 140.

If the line to be observed is one served by a line finder, key 200 is closed causing the energization of relay 218. It the line is an individual line or the lastline of a P. B. X. group, key 225 is opened as: sho-Wrigif any one but the last line` of a P.B. X. group, key 225 is closed. Relay 226, it VWillbe seen is connectedin parallel with relay 139. In the case of individual lines and last lines of a P. B. X. group, both windings of relay 139 are used, Whereas on all but the: last lines of a P. B. X. group only onewinding of relay 139 is used. Therefore, in order that relay 226 may operate in either case, the key 225 is provided to cutout the lhigh resistance Winding of relay 226, when only the 10W re-4 libero/46 sistancewinding of relays such as relay 139 is in use. y

When a call is initiated by the ksubscriber' of substation B, acircuit is closed which may be traced (from grounded battery, right hand Winding oi'. relay 207, inner right hand armature and back contact of relay 208, conl ductors 209, 131, 144, 118y through `substation B,`conductors 117, 143,132, 210, inner left hand armature andback contact or re-v lay 208, let hand Winding ci' relay l207 to ground. Relay 207 energizes, at its right hand armature closes an :obvious circuit for lamp 206, andv at its left hand armature closes a circuit which may be traced from grounded battery, winding of relay 147, inner left hand armature and back contact of relay 139., jumper Wire 148, conductors 142, 129., 211, lett-hand armature and front 'contact of relayv207, conductors 212, 130, 1141,

jumper Wire 149, right hand armature and back contact of relay 139 to ground. Relay 147 operates and starts the series of operations for causing an idle line inder to rind the cline, thus `connecting it toan idle 'dis` Winding of relay 230, armature and front contact of relay 231, conductors 217 and 216, inner right `hand armature and back contact of relay '215, outer left hand armature and back contact of relay 208, resistance 214 to grounded battery. Relay230; operates, closing an obvious circuit for lamp '205 and a substitute circuit for relay 231.

When the line finder has Jfound the line, battery from the districtselector on brush` 152 causes tlieoperation of relay 139, opening the circuit of relay147 and stopping the operation of the line finder. Battery on brush 152 by Way of conductors 145, 128, and 227, inner left hand armature and back contact of relay 215, inner kright hand ar1na. ture and front contact of relay 218, Winding of relay 226 to ground, causes the operation of this relay. The energization of relay 226 closes an obvious circuit for relay 232 Which upon energization closes a circuit from grounded battery, Winding of relay 208, right hand armature and front contact of relay 232 to ground, for energizing relay 208. At its left hand armature, relay 232 opens the circuit of relay 215 and places ground on the sleeves of test jacks 201, 202 and 203. The energization of relay `manently lighted.

208 as above, lights the lamp 204, opens the circuit of relays 207 and 230. Lamps 205 and 206 are extinguished, and relay 230 released. At the time relay 139 is released `on the completion of the call, relay 226 is Valso released, permitting the deenergization same sequence of operations as a regular call on which the subscriber fails to lthe saine lighting of thelamps;

dial and In this case also the brief energization of relay 207 alone causes a flash of the green lamp. A somewhat longer existence of the trouble would cause lthe energiz'ation'o'f relays 1117, 231 and 230 and thebrielighting of the green and whitela'mps, while a somewhat longer persistence of the trouble might light all three lamps as above outlinedbut allow tliered lamp to go out again. Inl the case of a line servedby a` linefinder theren is no stage at which the'white lamp is-per- If the groundor cross-conn`ection occurred within the central office, relay 14:7 would energize, starting the line `finder in operation, also connecting battery through relay 150 to relay 230, after which the operations are as above outlined. Lamp 205 is lighted momentarily vor lam-p 205 -and 204'in succession depending on the duration of the trouble.

If the line is selected as a called line, relay 139 is operated and the battery which causes the operation of relay 139 also, by way ott conductors 145, 128, 227 inner left hand` armature and back contact of relay 215, inner right hand armature and front contact of relay 218 and windings of relay 226 to ground. causes the energization of relav 226. which causes the energization of relay 232 and in turn the energization of .relay 208. lighting the red lamp tor indicate to the attendant that the line is busy.

If a test is attempted while the. line is busy, the energization of relay 232 holds onen the circuit of relay 215` sothat the insertion of a plug in one of the jacks 2011, 202, 203 will have no effect, but when. on the release of the apparatus. .relay 232 Jfalls baci-r. the circuit of relay 215" is completed an d the line made busy for testing purposes.

From the foregoing it will be seen that when the indicating circuits are connected to a line. the condition of the line will be shown as follows:

In case the subscriber at substation A or B initiates a call. the circuits function +o display green lamp 206 and white lamp 205 in succession momentarily. followed by red lamp 204. When the red lamp 204 lights, white lamp 205 and green lamp 206 vand red lamps in succession.

are' extinguished.` When the call is completed, the red lamp 204 goes out. Should substation A or B Vbe called, the `red lamp 204 is displayed.

A ground on the ring conductorof the line or a cross-connection between the line conductors, ifit existsl :tor an appreciable time, will cause the same set of signals to be displayed as on the regular call, the red lamp remaining lighted until thel central oiiice apparatus is released by the attendant.

A temporary ground will,f`according to y the time during whichit exists," cause a flash of the green lamp,` a flash ofthe greenland white lamps, or a Hash ofthe green, -white Where theline undergoing observation is served by a line switch, a ground or cross connection continuing long enough to start the hunting movement ofthe switch, but

not until an idle district selector has been found will cause the/white light lto remain lighted until kreleased bythe attendant.

Likewise la ground or cross-connectionv on the central ofiice equipment will, according -to vits duration, cause a flash of the white lamp or a successive temporary'lighting of the whiteand red lamps. v f

What is claimed is: 't n 1. In an automatic telephone exchange y system, subscribers lines, each served by one of two kinds of trunking` switches, means for indicating'unstandard conditions on `said lines, and a discriminating device operated in accordance with-thefkind ofswitch usedi to allow correct operation of said means.

2. In an automaticy telephone exchange system, individual subscribers lines, other subscribers lines arranged in groups, said lines served by trunking switches, means for indicating unstandard conditionsv on said lines, and a discriminating device operated to allow correct operation of said indicating means whether said means is associated with an individual line or with one of a of lines. f y

3. In an automatic telephone exchange system, subscribers lines, each served by one of two kinds of trunking switches, cen-v tral oiiice equipment associated with said subscribers lines, means for indicating unstandard conditions on said central otlice equipment, and a discriminating device operated in accordance with the kind of switch used to allow correct operation of said means.

4. In an automatic telephone exchange system, subscribers linesy adapted to be extended by automatic switches, vcentral oice y equipment `normally connected with said subscribers lines, and means for indicating unstandard conditions on said lines and on said central oiiice equipment, said means being operated in one manner to indicate an f unstandard condition on said line and in a being differently operated in accordance With the various durations of such unstandard conditions. e l y 6. In an automatic telephone exchange System, subscribers lines adapted to be -extended by automatic switches, central-,cnice equipment normally connected with said subscribers lines,- and means for indicating unstandard` conditions on saidfcentrall ofiice equipment, said means beingdilferently operated in' accordance with. thevvarious durations ofl such unstandard conditions.- y

7; In an automatic telephone exchange system, subscribers lines, central oifice equipment normally connected to saidisubscribers lines,- and alternative means for connecting said subscribers linesand said central oi'ce equipment, said connecting means including means differently operated toindicate unstandard conditions on'said lines, on said central office equipment, and' Various durations thereof.

8. In an automatic telephone, exchange system, sulfiscribersA lines adapted tobe extended. by automatic switches, l centi-'alf oflice equipment-v associated W-ith said lines,l .and

vmeans comprising; a Visual signal` for indi- ,eating unstandardconditions onsaid lines and said central oioe equipment, saidfsignal being operated in one manner to indicate an unstandard condition on said line andin a different manner toindicate anV unstandard conditionv ou said=central oiice equipment.l v

9. In an automatic telephone exchange system, subscribersv lines adapted to be extended by automatic switches, central oce equipment associated with said lines, and means comprising a visual signal for ndicating unstandardconditions on said lines, said signal being differentlyy operated in accordance with theY Various durations of said unstandard condition. e 4 I ,10. In an automatic 4telephone exchange system, subscribers.l lines adapted to be exment associated with saidr lines,andl avisual signal differently4 operated. yto indicatennstandard conditions on saidy lines, on said centralv ollice'. equipment, andvarious durationsthereof. f

In Witness whereof, I hereunto subscribe my name'thisQOth` day of October A. D.,

i922. l f DAVID L. TEMPLE. 

